ATMOS 100 EXAM 1 || A+ Verified Solutions.

Which gases are the primary constituents of the atmosphere? correct answers Nitrogen: 78% Oxygen: 20.9% What is the difference between weather and climate? correct answers Weather: the atmospheric conditions at a particular time and place. Temperature, pressure, humidity, cloud cover, precipitation, visibility, wind speed and direction. Climate: the average weather over a long period of time. What is the difference between satellites and radar? correct answers Satellites view clouds from space, radar views precipitation from the ground. How is wind direction defined? correct answers Identified by the direction from which the wind is blowing. A north wind blows from the north (to the south). Defines weather direction. Barbs identify wind speed: 1 barb=10 knots, half barb=5 knots, flag=50 knots. How do winds blow around high and low pressure systems in Northern Hemisphere? correct answers Low Pressure Systems: winds circulate counter-clockwise and inward High Pressure Systems: winds circulate clockwise and outward What is pressure and how does it change with height? correct answers Pressure: force per unit area (millibars) Pressure always decreases with height What is the average atmospheric pressure (in mb) at sea level? correct answers 1013.25 mb What is density and how does it change with height? correct answers Density: the amount of mass in a volume. Air density is the greatest at the surface and always decreases with height. Why is pressure corrected to sea level? correct answers Pressure variation with height is greater than pressure variation due to weather. Need to remove this variation with altitude to get meaningful picture of weather. Lapse rate correct answers The rate at which the temperature decreases with height Inversion correct answers the layer in which the temperature increases with height Troposphere correct answers The lowest layer of the atmosphere where all of the earth's weather happens. Layers of the Atmosphere correct answers Troposphere: very cold, difficult to breath Stratosphere: Contains ozone layer, absorbs UV radiation, warming the atmosphere. Mesosphere: Middle atmosphere. Lack of ozone, thin air. Thermosphere: Oxygen absorbs gamma rays and cosmic rays. Thin air, will freeze.